Excel BI - Excel Challenge 880

🔰 İnputs Results Depending upon the input in column A, write a formula to generate the given grid.

Illustration for Excel BI - Excel Challenge 880

Challenge Description

🔰 İnputs Results Depending upon the input in column A, write a formula to generate the given grid. Sample cases shown for 1, 2, 4 & 7.

Solutions

R Solution

layer_matrix <- function(n) {
  outer(1:(2 * n - 1), 1:(2 * n - 1), function(i, j) {
    pmax(abs(i - n), abs(j - n)) + 1
  })
}

print(layer_matrix(2))
print(layer_matrix(4))
print(layer_matrix(7))

R Analysis

• Logic: Apply the workbook rule directly and return the expected output shape.
• Strengths: The code maps the workbook rule into a compact, reproducible pipeline.
• Areas for Improvement: The approach is compact, but it depends on the workbook following the same input structure as the supplied challenge file.
• Gem: The elegant part is how little code is needed once the correct intermediate representation is chosen.

Python Solution

import numpy as np

def layer_matrix(n):
    size = 2 * n - 1
    mat = np.fromfunction(lambda i, j: np.maximum(np.abs(i - (n - 1)), np.abs(j - (n - 1))) + 1, (size, size), dtype=int)
    return mat.astype(int)

print(layer_matrix(2))
print(layer_matrix(4))
print(layer_matrix(7))

Python

The Python version mirrors the same workbook logic with a concise, direct implementation.

Difficulty Level

Easy / Medium

The business rule is clear, though the workbook still needs a few transformation steps to reach the expected output.

Related Challenges

• Excel Challenge 881
• Excel Challenge 882
• Excel Challenge 883